The Del Air Rockhounds Club, Inc
Los Angeles - San Fernando Valley, California, United States
- We are a non-profit organization dedicated to sharing knowledge of the lapidary arts and techniques, geology, mineralogy and related fields.

Northridge United Methodist
Church - 9650 Reseda Blvd, Northridge, CA 91324Guests are always welcome
at our meetings and events however our annual Holiday Party in December
requires a prepaid reservation in advance.

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February 2018 Program:

"Tips
& Tricks at the Jewelers Bench"

Presented by: Bradford Smith

(Bradford was unable to give
his presentation at our January meeting so he has kindly agreed to re-schedule
for February)

Bradford Smith
is a studio jeweler, lapidary, and jewelry instructor based in Santa Monica,
California. His teaching career started with eight years in the Los Angeles
school system. In 2009, he designed and built a new jewelry facility at Santa
Monica's Adult Education Center where he continues to teach Adult-Ed classes in
beginner to advanced jewelry fabrication

After retiring
and moving to California, Brad discovered rockhounding in the desert and the
lapidary arts. That led him to cutting gemstones, then to silversmithing, etc. He’s
been a happy camper ever since.

Brad is a long-time
member of the Culver City Rock Club, the Metal Arts Society of Southern
California, and the ASPCA. He enjoys photography, rockhounding, scuba diving
and robotics.

His how-to
jewelry book started nearly four years ago as a homework assignment in a social
media class. "Bench Tips for Jewelry Making" is now on Amazon, and has
more than 4700 followers on the Facebook Bench Tips page plus distribution to
213 club newsletters in six countries.

of all garnets
show a dominant dodecahedron or 12-sided form. The same collector may have
troubles

with garnet’s
intermingling with sister garnets, “isomorphous replacement”, but there are now
six

species, with
varieties, that can supply the collector with every color of the rainbow except
blue.

Accepted
variety names serve to identify variations in garnet species usually by source
or particular site- specific color, e.g. hessonite is ‘the cinnamon stone of Ceylon” and tsavorite is the emerald green

grossular
garnet.

Collectors who
wish to display crystals in matrix specimen frequently find that given a close
trimming,

garnet will pop
out of the matrix, leaving a perfect impression of its crystal faces in the
matrix. The

crystal will
have grown in its matrix, say a biotite schist, by pushing aside the biotite.
Forming out of

other iron and
aluminum bearing minerals being metamorphosed, the garnet’s tremendous power to
form

perfect crystal
faces is the outward manifestation of its complicated but highly symmetrical
internal

structure that
pushes aside minerals with weaker crystallization.

Garnet has a
hardness ranging from 6.5 to 7.5 on the Mohs scale. This makes them very
useful. When

found in
massive deposits, it is sold and used as an abrasive material. Harder than
quartz and parting

rather than
fracturing, it exceeds quartz sand for grinding material. Garnets have
considerable internal

strain, which
causes them to act like crystals of lesser symmetry and show anomalous
birefringence,

going from
light to dark in an erratic fashion when rotated between crossed polars.

BRUNEAU JASPERBruneau Jasper is a well-known beautiful stone that
comes from the region near the Bruneau River in western Idaho, about 30 miles
south of the tiny town of Bruneau. It is sometimes referred to as a

porcelain jasper because the cabochons
have such a nice porcelain-like finish. The Bruneau Jasper flow is the most
silica-rich rhyolite flow in the area. It is predominantly red and brown
jasper. The deposit covers several hundred meters and is covered with
unpatented claims. Jasper has a hardness of about 7 on the Moh's scale.

The Bruneau Woodpile site has long been popular among
fossil collectors; however, the deposit has received scant attention from
scientists. The fossilized wood was deposited ca. 6.85 Ma, within the Chalk
Hills Formation, and was mineralized with carbonate-fluorapatite. The diverse
assemblage of conifers and hardwoods is representative of the warm temperate
forests that flourished in southwest Idaho during the late Miocene. Limb and
trunk fragments preserved in a single thin sandstone bed appear to represent
woody debris that was transported by streams.(re-printed from the
Jan 2018 Petrograph – Peninsula Gem & Mineral Society)

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Mitchell Caverns

Mitchell Caverns is located within the
Providence Mountains State Recreation Area. Tours of the caves are offered
(twice a day Fridays, Saturdays and Sundays, and on Holiday Mondays) by
reservation only. Reservations can be made only by speaking to a staff member
on Mondays (8AM-5PM, 760-928-2586). The state recreation area is surrounded by
the Mojave National Preserve, which offers campgrounds (Hole-in-the-Wall is the
nearest) and roadside camping. At Hole-in-the-Wall, the Rings Loop Trail,
descending into Banshee Canyon by metal rings set into the rock, is exciting
for kids of all ages. (reprinted
from Delvings – Delvers Gem & Mineral Society)